Reflex Angle definition - Math Open Reference (original) (raw)

Reflex angle

Definition: An angle whose measure is greater than 180° and less than 360°

Try thisAdjust the angle below by dragging an orange dot and see how the angle ∠ABC behaves. Note that it is a reflex angle only when it is between 180° and a full circle.

Some might argue than reflex angles are not real. They are the 'other half' of a smaller angle. Indeed if you refer to the angle ∠ABC without qualifying it,it is generally assumed that you mean the smallest angle. If you mean the large part of the angle, you must specify it by saying 'reflex angle ∠ABC'.

Types of angle

Altogether, there are six types of angle as listed below. Click on an image for a full description of that type and a corresponding interactive applet.


Acute angleLess than 90°	Right angleExactly 90°	Obtuse angleBetween 90° and 180°

Straight angleExactly 180°	Reflex angleBetween 180° and 360°	Full angleExactly 360°

Reflex Angle definition - Math Open Reference (original) (raw)

Types of angle

Other angle topics

General

Angle Types

Angle relationships